Days after United Bank of India declared Kingfisher Airlines, promoter Vijay Mallya and three other directors wilful defaulters, country's largest bank SBI today said it has also sent a notice to tag them as "wilful defaulters".

"We have already sent a notice to KFA (to declare it as wilful defaulter). There is a mandatory time that needs to be given to them to respond and that time is currently on," said Arundhati Bhattacharya, Chairperson of SBI.

SBI, which is the lead bank of a lender consortium to the crippled carrier, has an exposure of over Rs 1,600 crore.

The airline owes Rs 7,600 crore to 17 banks. In February 2012, the banks had formally declared loan recall on KFA and began recovery process.

So far, they have recovered around Rs 2,000 crore by selling pledged shares. They are now working on selling two other pledged properties - Kingfisher Villa in Goa and Kingfisher House in Mumbai.

Already, United Bank of India has won a legal backing on its decision to declare Mallya and other top executives of the airline as wilful defaulters. State-run PNB and IDBI Bank, and private lenders Federal Bank and Axis Bank are also in the process of doing the same.

PNB, which has around Rs 800 crore to recover from the airline, and wants to tag the company as a wilful defaulter, has approached a Division Bench of Delhi High Court to stay a single Judge order that has allowed Mallya to send his lawyers to present his case.

According to banking norms, a defaulting borrower has to be personally present in the bank that seeks to declare him /her as wilful defaulter and can't be represented through lawyers. Citing the same, the Calcutta High Court upheld United Bank's decision on Mallya.

Asked about why SBI, the consortium leader that has the largest exposure to the airline, has been silent on the issue, she said, "Whatever is required to be done is being done. The process is already on but we don't want to talk about any particular account in public as we would prefer working silently."

Meanwhile, debt-ridden Kingfisher Airlines today contested UBI's decision to declare it as a wilful defaulter, saying that RBI guidelines in this regard do not apply to the company.

"Where they need to be stopped, we have done everything. If a regulator, whether Sebi or RBI, needs to know they all know everything," Bhattacharya told PTI in an interview here.

She said banks have to follow processes to defend themselves in case Kingfisher goes to court. "We have to be very sure ourselves that we can stand in a court of law in case he goes to court, and defend our action."

Calling for better recovery mechanism backed by law and not just by RBI norms, Bhattacharya said India needs a bankruptcy law.

"I personally believe we need much stronger laws for recovery and much better bankruptcy laws. The laws which we have at present are falling short of the requirement.

"The wilful defaulter tag is in RBI regulation but the force of law is not with it. So, you need a legal mandate there," Bhattacharya, who is completing her first year as the 208-year-old bank's first woman chief, said.

Asked why don't banks bunch all cases against KFA into a superior court, she said "It is being bundled as single case on behalf of the consortium. But declaring a borrower as a wilful defaulter can be done only by individual banks and not the consortium. This is legal requirement."

Kingfisher, which stopped flying since October 2012, owes as much as Rs 7,600 crore in principal and interest accrued since January 2012 to 17 banks. Among them, Punjab National Bank and IDBI Bank have Rs 800 crore exposure each.